Personal computer systems have attained widespread use for providing computer power to many segments of today's modern society. Personal computer systems have heretofore been defined as a desk top, floor standing, or portable microcomputer that consists of a system unit having a single system processor and associated volatile and non-volatile memory, a display monitor, a keyboard, one or more diskette drives, a fixed disk storage, and an optional printer. One of the distinguishing characteristics of these systems is the use of a motherboard or system planar to electrically connect these components together. These systems are designed primarily to give independent computing power to a single user and are inexpensively priced for purchase by individuals or small businesses. Examples of such personal computer systems are IBM's PERSONAL COMPUTER AT; compatible computers offered by competitors of IBM; and IBM's PERSONAL SYSTEM/2 Models 25, 30, 50, 60, 70 and 80.
These systems can be classified into two general families. The first family, usually referred to as Family I Models, use a bus architecture exemplified by the IBM PERSONAL COMPUTER AT and other "IBM compatible" machines. The second family, referred to as Family II Models, use IBM's MICRO CHANNEL bus architecture exemplified by IBM's PERSONAL SYSTEM/2 Models 50 through 80 and other MICRO CHANNEL machines. The Family I models typically have used the popular INTEL 8088, 8086, or 80286 microprocessor as the system processor. The 8088 and 8076 processors have the ability to address one megabyte of memory. The Family II models typically use the high speed INTEL 80286, 80386, and 80486 microprocessors which can operate in a real mode to emulate the slower speed INTEL 8086 microprocessor or a protected mode which extends the addressing range from 1 megabyte to 4 Gigabytes for some models. In essence, the real mode feature of the 80286, 80386, and 80486 processors provide hardware compatibility with software written for the 8086 and 8088 microprocessors.
Portable personal computers have recently advanced through developments which have been characterized as "luggable", to "laptop", and to "notebook". A "luggable" personal computer is one which is particularly configured to be fairly readily moved from one place to another, and which has a bulk and weight nearly the same as a more conventional desktop machine. A "laptop" personal computer is one which, while weighing about one half as much as and occupying less cubic volume than a luggable, is about the size and weight of a conventional business briefcase loaded with papers. A "notebook" personal computer typically is about the size of a conventional loose leaf binder holding letter size paper, and typically weighs about half as much as a laptop computer. As development of portable personal computers has advanced, substantially the full function of a more conventional desktop machine has been retained, with the exception that portable machines typically include a visual display integrated with the machine and users typically provide a separate printer which will be connected only as required.
A limitation on the reduction in the size of personal computers has been the desire of users for a keyboard at least approximating those known and used with desktop and floor standing machines. Such conventional keyboards typically have an elongated rectangular form with alphanumeric keys arrayed in rows and staggered columns and with special function keys appropriate to the personal computer arrayed around the alphanumeric keys in a standard array. Such keyboards may have varying numbers and arrangements of keys, and several such arrangements have become more or less conventional and known by the number of keys provided. As efforts have been expended toward reducing the physical size of portable personal computers, some designers have chosen to reduce the size of the keys and thus the keyboards, while others have chosen to eliminate or combine certain functions provided in more conventional keyboards. Such efforts have succeeded to the point that notebook portable personal computers have had some success in the marketplace, however users of such computers often have complaints about key size and keyboard arrangement as compared with more conventional keyboards used with desktop machines. Restraints on key size and arrangement have effectively imposed, prior to the present invention, a lower size limitation on keyboard length and width of about the size of a sheet of correspondence stationery.